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Amazon US · ASIN B08RX4QKXS

SANDISK 4TB Extreme Portable SSD (Old Model) - Up to 1050MB /s, USB-C, USB 3.2 Gen 2, IP65 Water and Dust Resistance, Updated Firmware - External Solid State Drive - SDSSDE61-4T00-G25 | 1050MB /s NVMe SSD with IP55 rating and AES encryption for photography, video capture and travel

The SanDisk Extreme Portable SSD 4TB is a high-capacity USB-C drive rated for up to 1050 MB/s reads and 1000 MB/s writes. A StorageReview test of a 1TB V2 unit measured 920.6 MB/s read, while a separate 1TB long-write test averaged 551 MB/s writes after its cache filled. Those family-level tests show useful context, but they are not direct measurements of this exact 4TB unit.

Updated 2026-09-27

SanDisk 4TB Extreme Portable SSD angled front view with carabiner loop
Available at Amazon

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Reviewer consensus

Single-source notes

  • Buyer fit: Agreed · 1/1 · [5]
  • Capacity and filesystem: Agreed · 1/1 · [4]
  • Durability and ingress: Agreed · 1/1 · [1]
  • Interface and cable: Agreed · 1/1 · [1]
  • Limitations: Weak point · 1/1 · [3]
  • Measured performance: Agreed · 1/1 · [5]
  • Platform compatibility: Agreed · 1/1 · [5]
  • Security and encryption: Agreed · 1/1 · [1]
  • Sequential transfer: Agreed · 2/2 · [4], [1]
  • Sustained performance: Agreed · 1/1 · [2]
  • Sustained write and cache: Weak point · 1/1 · [2]
  • Warranty and data recovery: Agreed · 1/1 · [5]

The review

SanDisk Extreme Portable SSD 4TB: speed, sustained writes and buyer fit

What the 4TB model offers

This model provides 4 TB of portable storage over USB-C and USB 3.2 Gen 2. Its listings rate sequential reads at up to 1050 MB/s and writes at up to 1000 MB/s. [4], [1]

Measured and sustained performance

StorageReview measured 920.6 MB/s reads on a V2 review unit. A separate long-write test of a V2 unit averaged 551 MB/s writes and reported that performance fell after the cache filled, so these family results are context rather than a guarantee for this exact model. [5], [2]

Field use and protection

An independent review identifies design professionals editing high-resolution photos and videos in the field as a suitable audience. The product listing also describes IP65 water and dust resistance and password protection with AES hardware encryption. [1], [5]

Compatibility and limitations

The V2 family is preformatted as exFAT for PC and Mac compatibility and carries a five-year warranty in the review evidence. Another review calls the included cable noticeably short, and the available evidence does not establish random I/O, efficiency or thermal-throttling results. [5], [3]

Buyer questions

Before you buy

How fast is the SanDisk Extreme Portable SSD 4TB?

The 4 TB listing rates up to 1050 MB/s reads and 1000 MB/s writes. StorageReview measured 920.6 MB/s reads on a V2 review unit, so that laboratory result should be treated as family context rather than a direct measurement of this exact model. [4], [1], [5]

Is it suitable for travel and field work?

The listing describes IP65 water and dust resistance, while an independent review identifies field editing of high-resolution photos and video as a target use. Environmental resistance does not replace a backup. [1], [5]

Compatibility

Can it be used with both PC and Mac?

The reviewed V2 family drive was preformatted as exFAT for PC and Mac compatibility. The evidence does not establish support for every operating-system version or device. [5]

Everyday use

Does it support password protection?

The exact-model listing describes password protection with 256-bit AES hardware encryption. [1]

Limitations

Does write speed stay constant during long transfers?

An available V2 family test averaged 551 MB/s writes and reported that performance dropped after the cache filled. The evidence does not directly measure this behavior on the exact model. [2]

What practical limitations should I know before buying?

A review describes the included cable as noticeably short. Separate review evidence states a five-year warranty, but the available sources do not establish random I/O, efficiency or thermal-throttling performance. [3], [5]

SanDisk 4TB Extreme Portable SSD angled front view with carabiner loop
SanDisk Extreme Portable SSD 4TB rugged external solid state drive with orange carabiner loopImage source: Western Digital Technologies, Inc.
SanDisk 4TB Extreme Portable SSD front direct view
Front profile of SanDisk Extreme Portable SSD 4TB with durable textured casingImage source: Western Digital Technologies, Inc.
SanDisk 4TB Extreme Portable SSD flat view showing USB-C port
Perspective view of SanDisk Extreme Portable SSD 4TB highlighting USB-C connection portImage source: Western Digital Technologies, Inc.

Facts and specifications

Retailer listing

SpecificationValueSource
EncryptionPassword protection with 256-bit AES hardware encryption[1]
InterfaceUSB-C with USB 3.2 Gen 2[1]
Sequential Read1050 MB/s[1]
Sequential Write1000 MB/s[4]
Storage Capacity4 TB[4]
Water ResistanceIP65 water and dust resistance with up to three-meter drop protection[1]

Stated by reviewers

SpecificationValueSource
File SystemPreformatted exFAT for PC and Mac compatibility[5]
WarrantyFive-year warranty[5]

Measured by a lab

SpecificationValueSource
Sequential Read920.6 MB/s[5]
Sequential Write551 MB/s[2]

Other facts

SpecificationValueSource
Buyer FitDesign professionals editing high-resolution photos and videos in the field[5]
LimitationIn the tested 1TB variant, the cache filled after about 5 GB and write performance was throttled; The included cable is noticeably short[3], [2]

Data: JSON · CSV

KnowSpec analysis

Is the SanDisk Extreme Portable SSD 4TB a good fit?

The SanDisk Extreme Portable SSD 4TB is a high-capacity USB-C drive rated for up to 1050 MB/s reads and 1000 MB/s writes. A StorageReview test of a 1TB V2 unit measured 920.6 MB/s read, while a separate 1TB long-write test averaged 551 MB/s writes after its cache filled. Those family-level tests show useful context, but they are not direct measurements of this exact 4TB unit.

Method: evidence_synthesis

Sustained transfer behavior

Short transfers can approach the product family's rated performance, but the available long-write evidence shows a clear cache boundary: the tested 1TB variant slowed once its cache filled. Buyers moving very large files should plan around sustained write behavior rather than headline burst figures.

Method: evidence_synthesis

Field-work strengths

The evidence supports mobile creative work: an independent review identifies field editing of high-resolution photos and video as a target use, while the listing describes IP65 resistance and password protection with AES hardware encryption.

Method: evidence_synthesis

Compatibility and practical limitations

The V2 family is preformatted as exFAT for PC and Mac use, and the review evidence states a five-year warranty. The included cable is described as noticeably short, so desk placement and port reach deserve attention before purchase.

Method: evidence_synthesis

Visible information gaps

Missing information is shown rather than guessed.

  • Topic:Thermal Throttlingnot found
  • Topic:Random Io And Latencynot found
  • Source.Manufacturernot public
  • Topic:Efficiencynot found

Sources and method

  1. SANDISK 4TB Extreme Portable SSD (Old Model) - Price HistoryPrice History · retrieved 2026-09-27Retailer listing
  2. TEST: SanDisk Extreme Portable SSD V2 1TB portable SSDSSD Tester · retrieved 2026-09-27Lab review
  3. SanDisk Extreme Portable SDD V2 reviewTech Advisor · retrieved 2026-09-27Editorial review
  4. SanDisk Extreme Portable SSD 4TB — price history & £/TBdisks.co.uk · retrieved 2026-09-27Retailer listing
  5. SanDisk Extreme Portable SSD V2 ReviewStorageReview · retrieved 2026-09-27Lab review
Updated: 2026-09-27 · Research accepted 2026-09-27Method: document and public-data analysis by an authorised research Agent with deterministic KnowSpec validation. No physical testing unless a section says otherwise. Missing or conflicting evidence stays visible instead of being guessed.